Differences between mRNA and DNA!

[Lottie]

Hi, I'm trying to catch up on all my A level biochemistry work I've missed. What are the four differences between mRNA and DNA molecules?
I've got mRNA is short lived so can change protein production to suit it's needs
and mRNA is small and can move out of the nucleus. But I'm stuck on the other two!

Thankyou!!!!!

[Nick]

Dunno if you still need it but:

mRNA is single stranded and contains nucleotide uricel
DNA is double stranded and contains nucleotide thymine

there are two other differences.

[abhay]

Hi Lottie
i can add few more points to that though its too late to mention:
-mRNA doesn't contain introns, which are abundantly present in DNA.
-mRNA contains polyA-tail necessary for its translation.

[Lottie]

Thanks for your replies, I'll keep checking, it's something I'm weak on, but thanks for what I've got now. It really helps!

Lottie x

[2810712]

here is a bit complicated difference,
During expression of DNA the product corresponding directly to DNA has same no, units, i.e. if a DNA strand of 30bases is transcribed then 30 RNA containing 30 bases is produced , while the product corresponding to mRNA in tralslation doesn't have equal no. of units i.e. polypeptide corresponding to mRNA of 30 bases will have 10 aminoacids [ units]

One obvious difference is- DNA can self replicate and RNA can not .

thanks,

hrushikesh